Gordon Ramsay’s father-in- law, who is battling the foul-mouthed chef for control of his restaurant empire, has been living a secret, double life with a second family and two children his family never knew about, according to reports.

Chris Hutcheson — the father of Ramsay’s wife, Tana, and, until last fall, Ramsay’s longtime business partner — has been keeping the secret for 30 years, the reports say.

The secret life came out only after Ramsay began having his father-in-law tailed by private detectives to gather evidence in a business dispute.

The details of Hutcheson’s secret life became public yesterday when they were splashed across several London newspapers, which have, until now, been legally prohibited from publishing the story.

The roots of Ramsay’s bitter break-up with his father-in-law last October had been something of a mystery until yesterday’s revelation.

The two men had been darlings of the restaurant world — transforming Ramsay from an up-and-coming London chef into an international TV superstar whose restaurants have been awarded a record 13 Michelin stars.

Suddenly, with a terse, lawyer-like statement, Ramsay announced Hutcheson’s firing last fall. Published reports at the time hinted that Hutcheson had borrowed more than $2 million from Ramsay’s company.

In one interview, Hutcheson called his son-in-law a “monster” who has been warped by his new celebrity lifestyle.

Ramsay shot back a week later. In an open letter — addressed to his estranged mother-in-law — Ramsay vaguely alluded to Hutcheson’s “complex life,” adding ominously that Hutcheson’s “away days were rarely what I thought they were.”

It now appears that, while trying to discover why his business partner had borrowed the large sum, detectives discovered Hutcheson’s secret second family.

Hutcheson had two children — Christopher, now 31, and Victoria, now 29 — with a British woman named Frances Collins, according to a report in the Daily Mail. He had paid for their upbringing and a series of lavish properties for their mother, the paper says.

Ramsay, through a spokesman, declined to comment yesterday.

A high-level UK judge removed the gag order yesterday that had prevented publication of the details of Hutcheson’s life before now.

Ramsay’s wife’s family has been split by the feud — with Hutcheson’s wife and son backing the father and Tana sticking with Gordon, with whom she has four kids.

Perhaps because of the family mess, the Ramsays have been spending more time at a mansion they’ve rented in LA recently — and word is that they may move to the US permanently.